A conventional electrical connector, as shown in FIGS. 5 and 6, are known from Japanese Patent No. JP 2001-143807 A.
FIG. 5 is a partially cutaway cross-sectional view showing a waterproof connector, while FIG. 6 is a partially cutaway cross-sectional view showing a terminal, which is being inserted into a cavity of the waterproof connector shown in FIG. 5.
A waterproof connector 100, shown in FIGS. 5 and 6, includes multiple terminals 110 (however, only one terminal is shown in FIGS. 5 and 6) and a connector housing 120 in which the terminals 110 are accommodated.
Each terminal 110 includes a receptacle 111 and a conductor grip 112, and is formed by stamping and forming a metal plate.
The receptacle 111 is configured to have a substantial box shape to receive a tab provided at the mating connector (not shown). The receptacle 111 includes a base plate 113 that extends in the front-rear direction (the horizontal direction of FIG. 5), a pair of side walls 114 that stand up from both side edges in the widthwise direction (the direction perpendicular to the sheet face of FIG. 5) of the base plate 113, and an upper plate 115 that is bent from one of the pair of side walls 114.
The conductor grip 112 includes: a conductor barrel 116, which extends from the rear end of the base plate 113 and which crimps a conductor S of an covered electrical wire W, and an insulation grip 117, which extends from the rear end of the conductor barrel 116 and which crimps an insulation portion H of the covered electrical wire W.
In this situation, in order to ensure electrical and mechanical connections, the conductor barrel 116 should be crimped to the conductor S over the entire length in its inserting/extracting direction (the horizontal direction of FIG. 5). Hence, the conductor S of the covered electrical wire W is crimped to the conductor barrel 116 with its end T protruding frontward from the conductor barrel 116.
The connector housing 120 is provided with multiple cavities 121 in two stages, namely upper and lower stages, into which the terminals 110 are accommodated, respectively.
On the rear side of multiple cavities 121 in the connector housing 120, there is provided a sealing member fitting portion 123 into which a sealing member 122 is fit and inserted.
The sealing member 122 is provided with multiple through-holes 124 that align with the cavities 121, respectively. In addition, three ribs 125 are arranged at the inner circumferential surface in each of the through-holes 124.
Then, in the waterproof connector 100 as shown in FIG. 6, each terminal 110 is inserted into each cavity 121 from each through-hole 124 in the sealing member 122. This allows the respective ribs 125 of the sealing member 122 to be tight around the covered electrical wire W of the terminal 110 that has been inserted into the through-hole 124, thereby preventing any water from entering the interior of the cavity 121 from the extracting side of the covered electrical wire W.
It should be noted, however, that in the terminal 110 of the waterproof connector 100, the end T of the conductor protrudes frontward to be exposed from the conductor barrel 116. Accordingly, in a case where the end T of the conductor S of the covered electrical wire W protrudes frontward to be exposed from the conductor barrel 116, there is a problem that the end T will damage the sealing member 122 when the terminal 110 is inserted into the through-hole 124 of the sealing member 122. Then, if the sealing member 122 is damaged, tightness between the sealing member 122 and the covered electrical wire W will be compromised. This will degrade the waterproof property in the cavity 121, when the waterproof connector 100 mates with the mating connector.
Therefore, a terminal shown in FIG. 7 has been proposed to address the above problem.
FIG. 7 is a perspective view showing a terminal in which an end portion of a core wire is protected.
A terminal 130, in which an end of a conductor is protected, as shown in FIG. 7, basically has the same configuration as that of the terminal 110, and is formed by stamping and forming a metal plate. However, a retainer catch 137, to be locked by a retainer (not shown) when the terminal 130 is included in an electrical connector (not shown), is provided at the upper surface of a receptacle 136 of the terminal 130.
Also, a conductor barrel 131 of the terminal 130 is provided with a crimping portion 132 that crimps the conductor of the covered electrical wire W (not shown in FIG. 7), and an extension 133 that covers the end of the conductor S of the covered electrical wire W.
The extension 133 is arranged on the front side of the crimping portion 132. The extension 133 is provided with a confirmation hole 134.
The confirmation hole 134 is provided for confirming the position of the end of the conductor in the conductor barrel 131 with the conductor of the covered electrical wire W crimped to the conductor barrel 131.
Additionally, in the terminal 130, the crimping portion 132 of the conductor barrel 131 crimps the conductor of the covered electrical wire W, and at the same time, the extension 133 covers the end portion of the conductor. In this manner, the extension 133 covers the end of the conductor of the covered electrical wire W, thereby preventing the end of the conductor from protruding frontward to be exposed from the conductor barrel 131.
Accordingly, with the terminal 130, it is possible to prevent the end of the conductor from damaging the sealing member 122, when the terminal 130 is inserted into the sealing member provided in the connector housing 120 shown in FIG. 5.
Moreover, after the crimping of the conductor of the covered electrical wire W to the conductor barrel 131 is completed, the position of the end of the conductor in the conductor barrel 131 is confirmed from the confirmation hole 134 of the extension 133. This makes it possible to confirm whether or not the conductor is crimped over the entire length in the inserting/extracting direction of the crimping portion 132 (the direction from the left near side to the right far side of FIG. 7).
In this case, the conductor of the covered electrical wire W is crimped to the conductor barrel 131, by pressing the conductor barrel 131 with an anvil and a crimper to swage the conductor barrel 131 in which the conductor is arranged.
Meanwhile, the length of the conductor barrel 131 in the front-rear direction (the direction from the left near side to the right far side of FIG. 7) in the terminal 130 is longer than the conductor barrel 116 in the terminal 110 shown in FIG. 6 by only the provision of the extension 133 in its length. If the conductor barrel 131 is longer, a greater pressing force is needed for swaging the conductor barrel 131 when the conductor of the covered electric wire W is crimped. Next, if the pressing force exerted from the anvil and the crimper to the conductor barrel 131 is greater, a reaction force exerted from the conductor barrel 131 to the anvil and the crimper will be greater when the conductor of the covered electric wire W is crimped. Then, if the reaction force exerted on the anvil and the crimper is greater when the conductor of the covered electric wire W is crimped, there is a problem that abrasion will be caused at the anvil and the crimper.
Hence, in order to address the above problem, the conductor of the covered electrical wire W is crimped to the conductor barrel 131 by a crimping tool 140 shown in FIG. 8.
FIG. 8 is a partial cross-sectional view showing the relationship between a conductor barrel of a terminal, and an anvil and a crimper included in the crimping tool. FIG. 8 shows a state where the crimping of the conductor of the covered electrical wire W to the conductor barrel 131 is completed.
That is to say, as shown in FIG. 8, the crimping tool 140 is provided with an anvil 141 that supports the conductor barrel 131 from the bottom side, and a crimper 142 that presses the conductor barrel 131 from the top side.
The lower surface of the crimper 142 has a pressing surface 143 that presses the conductor barrel 131. As shown in FIG. 8, the pressing surface 143 of the crimper 142 has a portion for pressing the extension 133, which is formed as an inclined surface 144 expanding and opening frontward.
When the conductor of the covered electrical wire (not shown in FIG. 8) is crimped to the conductor barrel 131 by the crimping tool 140, the extension 133 of the conductor barrel 131 is deformed along the inclined surface 144 of the pressing surface 143 in the crimper 142 and then an upthrust portion 145 is formed.
Thus, in the crimping tool 140, the conductor of the covered electrical wire W is crimped only to the crimping portion 132 in the conductor barrel 131, whereas the conductor is not crimped to the extension 133 because the upthrust portion 145 is formed. Accordingly, with the use of the crimping tool 140, the pressing force needed for crimping the conductor of the electric wire W to the conductor barrel 131 can be suppressed, so the reaction force exerted from the conductor barrel 131 to the anvil 141 and the crimper 142 can be suppressed.
Therefore, the crimping tool 140 is capable of suppressing abrasion caused at the anvil 141 and the crimper 142.
In this sense, when the terminal 130 is included in an electrical connector, the terminal 130 is secondarily locked by a retainer (not shown) to prevent the terminal 130 from dislodging from a connector housing (not shown). In such a case, the retainer is disposed above the conductor barrel 131 of the terminal 130, so the front surface of a locking portion (not shown) provided at the retainer locks the rear surface of the retainer catch 137 of the terminal 130, whereby the rearward movement of the terminal 130 is prevented.
Meanwhile, in recent years, there has been an increasing need for downsizing the electrical connector and increasing the number of terminals. In order to downsize the electrical connector and increase the number of terminals, it is necessary to narrow the arrangement pitch between the terminals included in the electrical connector.
However, if the terminal 130, in which the conductor of the covered electrical wire is crimped to the conductor barrel 131 by the crimping tool 140, is applied to an electrical connector in which the arrangement pitch between the terminals is narrow, the upthrust portion 145 will interfere with the retainer. Next, if the upthrust portion 145 interferes with the retainer, the retainer cannot be pushed to a predetermined position of the housing, resulting in an insufficient lock by means of the retainer for locking the retainer catch 137 in the terminal 130. Then, if the lock between the retainer and the retainer catch 137 of the terminal 130 is insufficient, there is a problem that a desired retaining force of the terminal 130 will not be obtainable by means of the retainer.
Meanwhile, when the terminal 130 is locked by the retainer, the terminal 130 is inserted into the housing with the terminal 130 disposed at a temporary locking position, firstly. In this case, the retainer is located above the conductor barrel 131 of the core-wire end-portion protected terminal 130 (at the upper side of FIG. 8). Subsequently, the retainer at the temporary locking position is made to slide downward (to the lower side of FIG. 8) to be disposed at a proper locking position. In this case, the front surface of a engaging portion in the retainer locks the rear surface of the retainer catch 137 of the terminal 130 to prevent the terminal 130 from moving rearward. Accordingly, in the sate where the retainer is located at the proper locking position, a space that corresponds to a sliding amount of the retainer that has been made to slide from the temporary locking position to the proper locking position is inevitably created below the conductor barrel 131 of the terminal 130.